How to subtract a Sum value from another sum value in SQL Server 2014?

Question

I need to subtract a sum of a field which follows condition 'A' from the sum of a field which follows condition 'B'

I've tried different combinations of code to try and get what I'm looking for. But I think the simplest, stupidest code is this one:

SELECT A.AccountNumber
      ,SUM(
      (SELECT SUM(FinTransAmt) 
           FROM FinTransMaster
           WHERE FinTransCode IN ('Code01', 'Code02', 'Code03', 'Code04')
       )
    -      -- Minus sign
      (SELECT SUM(FinTransAmt) 
           FROM FinTransMaster
       WHERE FinTransCode IN ('Code05', 'Code06', 'Code07', 'Code08')
       ) 
      ) AS Interest

FROM FinTransMaster ft
   , Account a 

WHERE ft.AcctID=a.AccountId 
  AND a.AccountNumber = '101010101'
  AND CAST (ft.Created as date) >= '2017-06-01'
  AND CAST (ft.Created as date) <= '2017-07-01'

GROUP BY A.AccountNumber

Answer 1

Perhaps another option

SELECT A.AccountNumber
      ,Interest = IsNull(SUM( case when FinTransCode IN ('Code01', 'Code02', 'Code03', 'Code04')  then FinTransAmt end),0)
                - IsNull(SUM( case when FinTransCode IN ('Code05', 'Code06', 'Code07', 'Code08')  then FinTransAmt end),0)
FROM FinTransMaster ft
   , Account a 
WHERE ft.AcctID=a.AccountId 
  AND a.AccountNumber = '101010101'
  AND CAST (ft.Created as date) >= '2017-06-01'
  AND CAST (ft.Created as date) <= '2017-07-01'
GROUP BY A.AccountNumber